// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/command_line.h"
#include "base/memory/scoped_vector.h"
#include "base/message_loop.h"
#include "base/stringprintf.h"
#include "base/time.h"
#include "chrome/browser/prerender/prerender_contents.h"
#include "chrome/browser/prerender/prerender_handle.h"
#include "chrome/browser/prerender/prerender_link_manager.h"
#include "chrome/browser/prerender/prerender_manager.h"
#include "chrome/browser/prerender/prerender_origin.h"
#include "chrome/common/chrome_switches.h"
#include "chrome/test/base/testing_browser_process.h"
#include "chrome/test/base/testing_profile.h"
#include "content/public/browser/render_view_host.h"
#include "content/public/test/test_browser_thread.h"
#include "googleurl/src/gurl.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "ui/gfx/size.h"

using base::Time;
using base::TimeDelta;
using base::TimeTicks;
using content::BrowserThread;
using content::Referrer;

namespace prerender {

class UnitTestPrerenderManager;

namespace {

class DummyPrerenderContents : public PrerenderContents {
 public:
  DummyPrerenderContents(UnitTestPrerenderManager* test_prerender_manager,
                         PrerenderTracker* prerender_tracker,
                         const GURL& url,
                         Origin origin,
                         FinalStatus expected_final_status);

  virtual ~DummyPrerenderContents() {
    EXPECT_EQ(expected_final_status_, final_status());
  }

  virtual void StartPrerendering(
      int ALLOW_UNUSED creator_child_id,
      const gfx::Size& ALLOW_UNUSED size,
      content::SessionStorageNamespace* ALLOW_UNUSED session_storage_namespace,
      bool is_control_group) OVERRIDE;

  virtual bool GetChildId(int* child_id) const OVERRIDE {
    *child_id = 0;
    return true;
  }

  virtual bool GetRouteId(int* route_id) const OVERRIDE {
    *route_id = 0;
    return true;
  }

  FinalStatus expected_final_status() const { return expected_final_status_; }

  bool prerendering_has_been_cancelled() const {
    return PrerenderContents::prerendering_has_been_cancelled();
  }

 private:
  UnitTestPrerenderManager* test_prerender_manager_;
  FinalStatus expected_final_status_;
};

const gfx::Size kSize(640, 480);

}  // namespace

class UnitTestPrerenderManager : public PrerenderManager {
 public:
  using PrerenderManager::kMinTimeBetweenPrerendersMs;
  using PrerenderManager::kNavigationRecordWindowMs;

  explicit UnitTestPrerenderManager(PrerenderTracker* prerender_tracker)
      : PrerenderManager(&profile_, prerender_tracker),
        time_(Time::Now()),
        time_ticks_(TimeTicks::Now()),
        next_prerender_contents_(NULL),
        prerender_tracker_(prerender_tracker) {
    set_rate_limit_enabled(false);
  }

  virtual ~UnitTestPrerenderManager() {
    if (next_prerender_contents()) {
      next_prerender_contents_.release()->Destroy(
          FINAL_STATUS_MANAGER_SHUTDOWN);
    }
    DoShutdown();
  }

  PrerenderContents* FindEntry(const GURL& url) {
    DeleteOldEntries();
    DeletePendingDeleteEntries();
    if (PrerenderData* data = FindPrerenderData(url, NULL))
      return data->contents();
    return NULL;
  }

  PrerenderContents* FindAndUseEntry(const GURL& url) {
    PrerenderData* prerender_data = FindPrerenderData(url, NULL);
    if (!prerender_data)
      return NULL;
    PrerenderContents* prerender_contents = prerender_data->contents();
    prerender_contents->set_final_status(FINAL_STATUS_USED);
    std::list<linked_ptr<PrerenderData> >::iterator to_erase =
        FindIteratorForPrerenderContents(prerender_contents);
    DCHECK(to_erase != active_prerender_list_.end());
    active_prerender_list_.erase(to_erase);
    prerender_contents->StartPendingPrerenders();
    return prerender_contents;
  }

  void AdvanceTime(TimeDelta delta) {
    time_ += delta;
  }

  void AdvanceTimeTicks(TimeDelta delta) {
    time_ticks_ += delta;
  }

  DummyPrerenderContents* CreateNextPrerenderContents(
      const GURL& url,
      FinalStatus expected_final_status) {
    DummyPrerenderContents* prerender_contents =
        new DummyPrerenderContents(this, prerender_tracker_, url,
                                   ORIGIN_LINK_REL_PRERENDER,
                                   expected_final_status);
    SetNextPrerenderContents(prerender_contents);
    return prerender_contents;
  }

  DummyPrerenderContents* CreateNextPrerenderContents(
      const GURL& url,
      Origin origin,
      FinalStatus expected_final_status) {
    DummyPrerenderContents* prerender_contents =
        new DummyPrerenderContents(this, prerender_tracker_, url,
                                   origin, expected_final_status);
    SetNextPrerenderContents(prerender_contents);
    return prerender_contents;
  }

  DummyPrerenderContents* CreateNextPrerenderContents(
      const GURL& url,
      const std::vector<GURL>& alias_urls,
      FinalStatus expected_final_status) {
    DummyPrerenderContents* prerender_contents =
        new DummyPrerenderContents(this, prerender_tracker_, url,
                                   ORIGIN_LINK_REL_PRERENDER,
                                   expected_final_status);
    for (std::vector<GURL>::const_iterator it = alias_urls.begin();
         it != alias_urls.end();
         ++it) {
      EXPECT_TRUE(prerender_contents->AddAliasURL(*it));
    }
    SetNextPrerenderContents(prerender_contents);
    return prerender_contents;
  }

  void set_rate_limit_enabled(bool enabled) {
    mutable_config().rate_limit_enabled = enabled;
  }

  PrerenderContents* next_prerender_contents() {
    return next_prerender_contents_.get();
  }

  // from PrerenderManager
  virtual Time GetCurrentTime() const OVERRIDE {
    return time_;
  }

  virtual TimeTicks GetCurrentTimeTicks() const OVERRIDE {
    return time_ticks_;
  }

 private:
  void SetNextPrerenderContents(DummyPrerenderContents* prerender_contents) {
    DCHECK(!next_prerender_contents_.get());
    next_prerender_contents_.reset(prerender_contents);
    if (prerender_contents->expected_final_status() == FINAL_STATUS_USED)
      used_prerender_contents_.push_back(prerender_contents);
  }


  virtual PrerenderContents* CreatePrerenderContents(
      const GURL& url,
      const Referrer& referrer,
      Origin origin,
      uint8 experiment_id) OVERRIDE {
    DCHECK(next_prerender_contents_.get());
    EXPECT_EQ(url, next_prerender_contents_->prerender_url());
    EXPECT_EQ(origin, next_prerender_contents_->origin());
    return next_prerender_contents_.release();
  }

  Time time_;
  TimeTicks time_ticks_;
  scoped_ptr<PrerenderContents> next_prerender_contents_;
  // PrerenderContents with an |expected_final_status| of FINAL_STATUS_USED,
  // tracked so they will be automatically deleted.
  ScopedVector<PrerenderContents> used_prerender_contents_;

  PrerenderTracker* prerender_tracker_;

  TestingProfile profile_;
};

class RestorePrerenderMode {
 public:
  RestorePrerenderMode() : prev_mode_(PrerenderManager::GetMode()) {
  }

  ~RestorePrerenderMode() { PrerenderManager::SetMode(prev_mode_); }
 private:
  PrerenderManager::PrerenderManagerMode prev_mode_;
};

DummyPrerenderContents::DummyPrerenderContents(
    UnitTestPrerenderManager* test_prerender_manager,
    PrerenderTracker* prerender_tracker,
    const GURL& url,
    Origin origin,
    FinalStatus expected_final_status)
    : PrerenderContents(test_prerender_manager, prerender_tracker,
                        NULL, url, Referrer(), origin,
                        PrerenderManager::kNoExperiment),
      test_prerender_manager_(test_prerender_manager),
      expected_final_status_(expected_final_status) {
}

void DummyPrerenderContents::StartPrerendering(
    int ALLOW_UNUSED creator_child_id,
    const gfx::Size& ALLOW_UNUSED size,
    content::SessionStorageNamespace* ALLOW_UNUSED session_storage_namespace,
    bool is_control_group) {
  // In the base PrerenderContents implementation, StartPrerendering will
  // be called even when the PrerenderManager is part of the control group,
  // but it will early exit before actually creating a new RenderView if
  // |is_control_group| is true;
  if (!is_control_group)
    prerendering_has_started_ = true;
  load_start_time_ = test_prerender_manager_->GetCurrentTimeTicks();
}

class PrerenderTest : public testing::Test {
 public:
  static const int kDefaultChildId = -1;
  static const int kDefaultRenderViewRouteId = -1;

  PrerenderTest() : ui_thread_(BrowserThread::UI, &message_loop_),
                    prerender_manager_(
                        new UnitTestPrerenderManager(prerender_tracker())),
                    prerender_link_manager_(
                        new PrerenderLinkManager(prerender_manager_.get())),
                    last_prerender_id_(0) {
    // Enable omnibox prerendering.
    CommandLine::ForCurrentProcess()->AppendSwitchASCII(
        switches::kPrerenderFromOmnibox,
        switches::kPrerenderFromOmniboxSwitchValueEnabled);
  }

  ~PrerenderTest() {
    prerender_link_manager_->OnChannelClosing(kDefaultChildId);
  }

  UnitTestPrerenderManager* prerender_manager() {
    return prerender_manager_.get();
  }

  PrerenderLinkManager* prerender_link_manager() {
    return prerender_link_manager_.get();
  }

  bool IsEmptyPrerenderLinkManager() {
    return prerender_link_manager_->IsEmpty();
  }

  int last_prerender_id() const {
    return last_prerender_id_;
  }

  int GetNextPrerenderID() {
    return ++last_prerender_id_;
  }

  // Shorthand to add a simple preload with a reasonable source.
  bool AddSimplePrerender(const GURL& url) {
    return prerender_link_manager()->OnAddPrerender(
        kDefaultChildId, GetNextPrerenderID(),
        url, content::Referrer(),
        kSize, kDefaultRenderViewRouteId);
  }

 private:
  PrerenderTracker* prerender_tracker() {
    return g_browser_process->prerender_tracker();
  }

  // Needed to pass PrerenderManager's DCHECKs.
  MessageLoop message_loop_;
  content::TestBrowserThread ui_thread_;
  scoped_ptr<UnitTestPrerenderManager> prerender_manager_;
  scoped_ptr<PrerenderLinkManager> prerender_link_manager_;
  int last_prerender_id_;
};

TEST_F(PrerenderTest, FoundTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
}

TEST_F(PrerenderTest, DuplicateTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  scoped_ptr<PrerenderHandle> duplicate_prerender_handle(
      prerender_manager()->AddPrerenderFromLinkRelPrerender(
          kDefaultChildId, kDefaultRenderViewRouteId, url,
          Referrer(url, WebKit::WebReferrerPolicyDefault), kSize));

  EXPECT_TRUE(duplicate_prerender_handle->IsValid());
  EXPECT_TRUE(duplicate_prerender_handle->IsPrerendering());

  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));

  EXPECT_FALSE(duplicate_prerender_handle->IsValid());
  EXPECT_FALSE(duplicate_prerender_handle->IsPrerendering());
}

// Make sure that if queue a request, and a second prerender request for the
// same URL comes in, that we drop the second request and keep the first one.
TEST_F(PrerenderTest, DropSecondRequestTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_USED);
  DummyPrerenderContents* null = NULL;
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  DummyPrerenderContents* prerender_contents1 =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_MANAGER_SHUTDOWN);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_EQ(prerender_contents1,
            prerender_manager()->next_prerender_contents());
  EXPECT_FALSE(prerender_contents1->prerendering_has_started());

  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
}

// Ensure that we expire a prerendered page after the max. permitted time.
TEST_F(PrerenderTest, ExpireTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_TIMED_OUT);
  DummyPrerenderContents* null = NULL;
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  prerender_manager()->AdvanceTimeTicks(
      prerender_manager()->config().time_to_live + TimeDelta::FromSeconds(1));
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
}

// When the user navigates away from a page, the prerenders it launched should
// have their time to expiry shortened from the default time to live.
TEST_F(PrerenderTest, LinkManagerNavigateAwayExpire) {
  const TimeDelta time_to_live = TimeDelta::FromSeconds(300);
  const TimeDelta abandon_time_to_live = TimeDelta::FromSeconds(20);
  const TimeDelta test_advance = TimeDelta::FromSeconds(22);
  ASSERT_LT(test_advance, time_to_live);
  ASSERT_LT(abandon_time_to_live, test_advance);

  prerender_manager()->mutable_config().time_to_live = time_to_live;
  prerender_manager()->mutable_config().abandon_time_to_live =
      abandon_time_to_live;

  GURL url("http://example.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(url,
                                                       FINAL_STATUS_TIMED_OUT);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               last_prerender_id());
  EXPECT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  DummyPrerenderContents* null = NULL;
  EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
  prerender_manager()->AdvanceTimeTicks(test_advance);

  EXPECT_EQ(null, prerender_manager()->FindEntry(url));
}

// But when we navigate away very close to the original expiry of a prerender,
// we shouldn't expect it to be extended.
TEST_F(PrerenderTest, LinkManagerNavigateAwayNearExpiry) {
  const TimeDelta time_to_live = TimeDelta::FromSeconds(300);
  const TimeDelta abandon_time_to_live = TimeDelta::FromSeconds(20);

  // We will expect the prerender to still be alive after advancing the clock
  // by first_advance. But, after second_advance, we expect it to have timed
  // out, demonstrating that you can't extend a prerender by navigating away
  // from its launcher.
  const TimeDelta first_advance = TimeDelta::FromSeconds(298);
  const TimeDelta second_advance = TimeDelta::FromSeconds(4);
  ASSERT_LT(first_advance, time_to_live);
  ASSERT_LT(time_to_live - first_advance, abandon_time_to_live);
  ASSERT_LT(time_to_live, first_advance + second_advance);

  prerender_manager()->mutable_config().time_to_live = time_to_live;
  prerender_manager()->mutable_config().abandon_time_to_live =
      abandon_time_to_live;

  GURL url("http://example2.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(url,
                                                       FINAL_STATUS_TIMED_OUT);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));

  prerender_manager()->AdvanceTimeTicks(first_advance);
  EXPECT_EQ(prerender_contents, prerender_manager()->FindEntry(url));

  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               last_prerender_id());
  EXPECT_EQ(prerender_contents, prerender_manager()->FindEntry(url));

  DummyPrerenderContents* null = NULL;
  EXPECT_EQ(null, prerender_manager()->next_prerender_contents());

  prerender_manager()->AdvanceTimeTicks(second_advance);
  EXPECT_EQ(null, prerender_manager()->FindEntry(url));
}

// LRU Test. Make sure that if we prerender more requests than we support, that
// the oldest one will be dropped.
TEST_F(PrerenderTest, DropOldestRequestTest) {
  std::vector<int> concurrencies_to_test;
  concurrencies_to_test.push_back(
      prerender_manager()->config().max_concurrency);
  concurrencies_to_test.push_back(1);
  concurrencies_to_test.push_back(2);

  DummyPrerenderContents* null = NULL;
  GURL url_to_evict("http://www.google.com/evictme");

  for (std::vector<int>::const_iterator i = concurrencies_to_test.begin();
       i != concurrencies_to_test.end();
       ++i) {
    const int max_concurrency = *i;
    prerender_manager()->mutable_config().max_concurrency = max_concurrency;

    DummyPrerenderContents* prerender_contents_to_evict =
        prerender_manager()->CreateNextPrerenderContents(
            url_to_evict, FINAL_STATUS_EVICTED);
    EXPECT_TRUE(AddSimplePrerender(url_to_evict));
    EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
    EXPECT_TRUE(prerender_contents_to_evict->prerendering_has_started());

    std::vector<GURL> urls;
    std::vector<PrerenderContents*> prerender_contentses;

    for (int j = 0; j < max_concurrency; ++j) {
      urls.push_back(GURL(base::StringPrintf("http://google.com/use#%d", j)));
      prerender_contentses.push_back(
          prerender_manager()->CreateNextPrerenderContents(urls.back(),
                                                           FINAL_STATUS_USED));
      EXPECT_TRUE(AddSimplePrerender(urls.back()));
      EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
      EXPECT_TRUE(prerender_contentses.back()->prerendering_has_started());
    }

    ASSERT_EQ(null, prerender_manager()->FindEntry(url_to_evict));
    for (int j = 0; j < max_concurrency; ++j) {
      ASSERT_EQ(prerender_contentses[j],
                prerender_manager()->FindAndUseEntry(urls[j]));
    }
  }
}

TEST_F(PrerenderTest, AliasURLTest) {
  GURL url("http://www.google.com/");
  GURL alias_url1("http://www.google.com/index.html");
  GURL alias_url2("http://google.com/");
  GURL not_an_alias_url("http://google.com/index.html");
  std::vector<GURL> alias_urls;
  alias_urls.push_back(alias_url1);
  alias_urls.push_back(alias_url2);

  // Test that all of the aliases work, but not_an_alias_url does not.
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, alias_urls, FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  ASSERT_EQ(NULL, prerender_manager()->FindEntry(not_an_alias_url));
  ASSERT_EQ(prerender_contents,
            prerender_manager()->FindAndUseEntry(alias_url1));
  prerender_contents = prerender_manager()->CreateNextPrerenderContents(
          url, alias_urls, FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  ASSERT_EQ(prerender_contents,
            prerender_manager()->FindAndUseEntry(alias_url2));
  prerender_contents = prerender_manager()->CreateNextPrerenderContents(
          url, alias_urls, FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));

  // Test that alias URLs can not be added.
  prerender_contents = prerender_manager()->CreateNextPrerenderContents(
          url, alias_urls, FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(AddSimplePrerender(alias_url1));
  EXPECT_TRUE(AddSimplePrerender(alias_url2));
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
}

// Ensure that we ignore prerender requests within the rate limit.
TEST_F(PrerenderTest, RateLimitInWindowTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_MANAGER_SHUTDOWN);
  DummyPrerenderContents* null = NULL;
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  prerender_manager()->set_rate_limit_enabled(true);
  prerender_manager()->AdvanceTimeTicks(TimeDelta::FromMilliseconds(1));

  GURL url1("http://news.google.com/");
  prerender_manager()->CreateNextPrerenderContents(
      url,
      FINAL_STATUS_MANAGER_SHUTDOWN);
  EXPECT_FALSE(AddSimplePrerender(url1));
  prerender_manager()->set_rate_limit_enabled(false);
}

// Ensure that we don't ignore prerender requests outside the rate limit.
TEST_F(PrerenderTest, RateLimitOutsideWindowTest) {
  // Setting concurrency to one lets us force eviction by adding only one more
  // prerender.
  prerender_manager()->mutable_config().max_concurrency = 1;

  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_EVICTED);
  DummyPrerenderContents* null = NULL;
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  prerender_manager()->set_rate_limit_enabled(true);
  prerender_manager()->AdvanceTimeTicks(
      TimeDelta::FromMilliseconds(
          UnitTestPrerenderManager::kMinTimeBetweenPrerendersMs + 500));

  GURL url1("http://news.google.com/");
  DummyPrerenderContents* rate_limit_prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url1,
          FINAL_STATUS_MANAGER_SHUTDOWN);
  EXPECT_TRUE(AddSimplePrerender(url1));
  EXPECT_EQ(null, prerender_manager()->next_prerender_contents());
  EXPECT_TRUE(rate_limit_prerender_contents->prerendering_has_started());
  prerender_manager()->set_rate_limit_enabled(false);
}

TEST_F(PrerenderTest, PendingPrerenderTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));

  int child_id;
  int route_id;
  ASSERT_TRUE(prerender_contents->GetChildId(&child_id));
  ASSERT_TRUE(prerender_contents->GetRouteId(&route_id));

  GURL pending_url("http://news.google.com/");

  DummyPrerenderContents* pending_prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          pending_url,
          ORIGIN_GWS_PRERENDER,
          FINAL_STATUS_USED);
  scoped_ptr<PrerenderHandle> pending_prerender_handle(
      prerender_manager()->AddPrerenderFromLinkRelPrerender(
          child_id, route_id, pending_url,
          Referrer(url, WebKit::WebReferrerPolicyDefault), kSize));
  DCHECK(pending_prerender_handle.get());
  EXPECT_TRUE(pending_prerender_handle->IsValid());
  EXPECT_TRUE(pending_prerender_handle->IsPending());

  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));

  EXPECT_FALSE(pending_prerender_handle->IsPending());
  ASSERT_EQ(pending_prerender_contents,
            prerender_manager()->FindAndUseEntry(pending_url));
}

TEST_F(PrerenderTest, InvalidPendingPrerenderTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));

  int child_id;
  int route_id;
  ASSERT_TRUE(prerender_contents->GetChildId(&child_id));
  ASSERT_TRUE(prerender_contents->GetRouteId(&route_id));

  // This pending URL has an unsupported scheme, and won't be able
  // to start.
  GURL pending_url("ftp://news.google.com/");

  prerender_manager()->CreateNextPrerenderContents(
      pending_url,
      ORIGIN_GWS_PRERENDER,
      FINAL_STATUS_UNSUPPORTED_SCHEME);
  scoped_ptr<PrerenderHandle> pending_prerender_handle(
      prerender_manager()->AddPrerenderFromLinkRelPrerender(
          child_id, route_id, pending_url,
          Referrer(url, WebKit::WebReferrerPolicyDefault), kSize));
  DCHECK(pending_prerender_handle.get());
  EXPECT_TRUE(pending_prerender_handle->IsValid());
  EXPECT_TRUE(pending_prerender_handle->IsPending());

  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));

  EXPECT_FALSE(pending_prerender_handle->IsValid());
  EXPECT_FALSE(pending_prerender_handle->IsPending());
}

TEST_F(PrerenderTest, CancelPendingPrerenderTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));

  int child_id;
  int route_id;
  ASSERT_TRUE(prerender_contents->GetChildId(&child_id));
  ASSERT_TRUE(prerender_contents->GetRouteId(&route_id));

  GURL pending_url("http://news.google.com/");

  scoped_ptr<PrerenderHandle> pending_prerender_handle(
      prerender_manager()->AddPrerenderFromLinkRelPrerender(
          child_id, route_id, pending_url,
          Referrer(url, WebKit::WebReferrerPolicyDefault), kSize));
  DCHECK(pending_prerender_handle.get());
  EXPECT_TRUE(pending_prerender_handle->IsValid());
  EXPECT_TRUE(pending_prerender_handle->IsPending());

  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  pending_prerender_handle->OnCancel();
  EXPECT_FALSE(pending_prerender_handle->IsValid());

  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
}

// Tests that a PrerenderManager created for a browser session in the control
// group works as expected.
TEST_F(PrerenderTest, ControlGroup) {
  RestorePrerenderMode restore_prerender_mode;
  PrerenderManager::SetMode(
      PrerenderManager::PRERENDER_MODE_EXPERIMENT_CONTROL_GROUP);
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_MANAGER_SHUTDOWN);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_FALSE(prerender_contents->prerendering_has_started());
}

// Tests that prerendering is cancelled when the source render view does not
// exist.  On failure, the DCHECK in CreatePrerenderContents() above should be
// triggered.
TEST_F(PrerenderTest, SourceRenderViewClosed) {
  GURL url("http://www.google.com/");
  prerender_manager()->CreateNextPrerenderContents(
      url,
      FINAL_STATUS_MANAGER_SHUTDOWN);
  EXPECT_FALSE(prerender_link_manager()->OnAddPrerender(
      100, GetNextPrerenderID(), url,
      Referrer(), kSize, 200));
}

// Tests that prerendering is cancelled when we launch a second prerender of
// the same target within a short time interval.
TEST_F(PrerenderTest, RecentlyVisited) {
  GURL url("http://www.google.com/");

  prerender_manager()->RecordNavigation(url);

  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_RECENTLY_VISITED);
  EXPECT_FALSE(AddSimplePrerender(url));
  EXPECT_FALSE(prerender_contents->prerendering_has_started());
}

TEST_F(PrerenderTest, NotSoRecentlyVisited) {
  GURL url("http://www.google.com/");

  prerender_manager()->RecordNavigation(url);
  prerender_manager()->AdvanceTimeTicks(
      TimeDelta::FromMilliseconds(
          UnitTestPrerenderManager::kNavigationRecordWindowMs + 500));

  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
}

// Tests that our PPLT dummy prerender gets created properly.
TEST_F(PrerenderTest, PPLTDummy) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_UNSUPPORTED_SCHEME);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  DummyPrerenderContents* pplt_dummy_contents =
      prerender_manager()->CreateNextPrerenderContents(url,
                                                       FINAL_STATUS_USED);
  GURL ftp_url("ftp://ftp.google.com/");
  // Adding this ftp URL will force the expected unsupported scheme error.
  prerender_contents->AddAliasURL(ftp_url);

  ASSERT_EQ(pplt_dummy_contents, prerender_manager()->FindAndUseEntry(url));
}

// Tests that our PPLT dummy prerender gets created properly, even
// when navigating to a page that has been recently navigated to.
TEST_F(PrerenderTest, RecentlyVisitedPPLTDummy) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_UNSUPPORTED_SCHEME);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  DummyPrerenderContents* pplt_dummy_contents =
      prerender_manager()->CreateNextPrerenderContents(url,
                                                       FINAL_STATUS_USED);
  prerender_manager()->RecordNavigation(url);
  GURL ftp_url("ftp://ftp.google.com/");
  prerender_contents->AddAliasURL(ftp_url);

  ASSERT_EQ(pplt_dummy_contents, prerender_manager()->FindAndUseEntry(url));
}

// Tests that the prerender manager matches include the fragment.
TEST_F(PrerenderTest, FragmentMatchesTest) {
  GURL fragment_url("http://www.google.com/#test");

  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(fragment_url,
                                                       FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(fragment_url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  ASSERT_EQ(prerender_contents,
            prerender_manager()->FindAndUseEntry(fragment_url));
}

// Tests that the prerender manager uses fragment references when matching
// prerender URLs in the case a different fragment is in both URLs.
TEST_F(PrerenderTest, FragmentsDifferTest) {
  GURL fragment_url("http://www.google.com/#test");
  GURL other_fragment_url("http://www.google.com/#other_test");

  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(fragment_url,
                                                       FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(fragment_url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());

  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(other_fragment_url));

  ASSERT_EQ(prerender_contents,
            prerender_manager()->FindAndUseEntry(fragment_url));
}

// Make sure that clearing works as expected.
TEST_F(PrerenderTest, ClearTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url,
          FINAL_STATUS_CACHE_OR_HISTORY_CLEARED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  prerender_manager()->ClearData(PrerenderManager::CLEAR_PRERENDER_CONTENTS);
  DummyPrerenderContents* null = NULL;
  EXPECT_EQ(null, prerender_manager()->FindEntry(url));
}

// Make sure canceling works as expected.
TEST_F(PrerenderTest, CancelAllTest) {
  GURL url("http://www.google.com/");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_CANCELLED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  prerender_manager()->CancelAllPrerenders();
  const DummyPrerenderContents* null = NULL;
  EXPECT_EQ(null, prerender_manager()->FindEntry(url));
}

TEST_F(PrerenderTest, OmniboxNotAllowedWhenDisabled) {
  prerender_manager()->set_enabled(false);
  EXPECT_FALSE(prerender_manager()->AddPrerenderFromOmnibox(
      GURL("http://www.example.com"), NULL, gfx::Size()));
}

TEST_F(PrerenderTest, LinkRelNotAllowedWhenDisabled) {
  prerender_manager()->set_enabled(false);
  EXPECT_FALSE(AddSimplePrerender(
      GURL("http://www.example.com")));
}

TEST_F(PrerenderTest, LinkManagerCancel) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_CANCELLED);

  EXPECT_TRUE(AddSimplePrerender(url));

  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              last_prerender_id());

  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
}

TEST_F(PrerenderTest, LinkManagerCancelThenAbandon) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_CANCELLED);

  EXPECT_TRUE(AddSimplePrerender(url));

  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              last_prerender_id());

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               last_prerender_id());

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
}

// TODO(gavinp): Re-enabmed this test after abandon has an effect on Prerenders,
// like shortening the timeouts.
TEST_F(PrerenderTest, LinkManagerAbandon) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_USED);

  EXPECT_TRUE(AddSimplePrerender(url));

  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               last_prerender_id());

  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
}

TEST_F(PrerenderTest, LinkManagerCancelTwice) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_CANCELLED);

  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              last_prerender_id());

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              last_prerender_id());
}

TEST_F(PrerenderTest, LinkManagerAddTwiceCancelTwice) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_CANCELLED);

  EXPECT_TRUE(AddSimplePrerender(url));

  const int first_prerender_id = last_prerender_id();
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  EXPECT_TRUE(AddSimplePrerender(url));

  const int second_prerender_id = last_prerender_id();
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              first_prerender_id);

  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              second_prerender_id);

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
}

TEST_F(PrerenderTest, LinkManagerAddTwiceCancelTwiceThenAbandonTwice) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_CANCELLED);

  EXPECT_TRUE(AddSimplePrerender(url));

  const int first_prerender_id = last_prerender_id();
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  EXPECT_TRUE(AddSimplePrerender(url));

  const int second_prerender_id = last_prerender_id();
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              first_prerender_id);

  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              second_prerender_id);

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               first_prerender_id);

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               second_prerender_id);

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(prerender_contents->prerendering_has_been_cancelled());
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
}

// TODO(gavinp): Update this test after abandon has an effect on Prerenders,
// like shortening the timeouts.
TEST_F(PrerenderTest, LinkManagerAddTwiceAbandonTwice) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_USED);

  EXPECT_TRUE(AddSimplePrerender(url));

  const int first_prerender_id = last_prerender_id();
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  EXPECT_TRUE(AddSimplePrerender(url));

  const int second_prerender_id = last_prerender_id();
  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               first_prerender_id);

  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                               second_prerender_id);

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
}

// TODO(gavinp): After abandon shortens the expire time on a Prerender,
// add a series of tests testing advancing the time by either the abandon
// or normal expire, and verifying the expected behaviour with groups
// of links.
TEST_F(PrerenderTest, LinkManagerExpireThenCancel) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_TIMED_OUT);

  EXPECT_TRUE(AddSimplePrerender(url));

  EXPECT_TRUE(prerender_contents->prerendering_has_started());
  EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(prerender_contents, prerender_manager()->FindEntry(url));
  prerender_manager()->AdvanceTimeTicks(
      prerender_manager()->config().time_to_live + TimeDelta::FromSeconds(1));

  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              last_prerender_id());

  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
}

TEST_F(PrerenderTest, LinkManagerExpireThenAddAgain) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* first_prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_TIMED_OUT);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(first_prerender_contents->prerendering_has_started());
  EXPECT_FALSE(first_prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(first_prerender_contents,
            prerender_manager()->FindEntry(url));
  prerender_manager()->AdvanceTimeTicks(
      prerender_manager()->config().time_to_live + TimeDelta::FromSeconds(1));
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
  DummyPrerenderContents* second_prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(second_prerender_contents->prerendering_has_started());
  ASSERT_EQ(second_prerender_contents,
            prerender_manager()->FindAndUseEntry(url));
  // The PrerenderLinkManager is not empty since we never removed the first
  // prerender.
  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
}

TEST_F(PrerenderTest, LinkManagerCancelThenAddAgain) {
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  GURL url("http://www.myexample.com");
  DummyPrerenderContents* first_prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_CANCELLED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(first_prerender_contents->prerendering_has_started());
  EXPECT_FALSE(first_prerender_contents->prerendering_has_been_cancelled());
  ASSERT_EQ(first_prerender_contents, prerender_manager()->FindEntry(url));
  prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                              last_prerender_id());
  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
  EXPECT_TRUE(first_prerender_contents->prerendering_has_been_cancelled());
  DummyPrerenderContents* null = NULL;
  ASSERT_EQ(null, prerender_manager()->FindEntry(url));
  DummyPrerenderContents* second_prerender_contents =
      prerender_manager()->CreateNextPrerenderContents(
          url, FINAL_STATUS_USED);
  EXPECT_TRUE(AddSimplePrerender(url));
  EXPECT_TRUE(second_prerender_contents->prerendering_has_started());
  ASSERT_EQ(second_prerender_contents,
            prerender_manager()->FindAndUseEntry(url));
  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
}

}  // namespace prerender